Fix logging in tests for Boot 3.1.x.

Author: OlgaMaciaszek

spring-cloud-loadbalancer/src/test/resources/logback-test.xml

@@ -0,0 +1,11 @@
+<configuration>
+	<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+		<encoder>
+			<pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
+		</encoder>
+	</appender>
+
+	<root level="debug">
+		<appender-ref ref="STDOUT" />
+	</root>
+</configuration>